1. Field of the Invention
This invention relates to an integrated circuit device and to electronic equipment such as a computer having the circuit device.
2. Description of the Related Art
The performance and reliability of integrated circuit devices are closely related to the temperatures of the circuit devices. Likewise, the performance and reliability of electronic equipment including a plurality of printed circuit boards each having a large number of integrated circuit devices of the above type mounted thereon is dependent on the temperature characteristics thereof. Such electronic equipment includes the CPU of a computer system, various terminal devices, and communication devices, for example.
Conventionally, this type of electronic equipment includes a plurality of printed circuit boards arranged in a frame and each having a large number of integrated circuit devices mounted thereon. Further, in the frame, a forced cooling means is provided. The forced cooling means is used to control the temperatures of the integrated circuit devices in the electronic equipment (frame) within a limited temperature range. As the forced cooling means, a duct and fan are provided. For example, an air inlet duct is provided in the front surface portion of a casing and a fan is disposed on the upper portion of the casing to provide a casing structure which creates a forced air flow in the casing. Circuit boards having integrated circuits mounted thereon are placed in the forced air flow so as to attain forced air cooling for the circuit boards.
Conventionally, the temperature control of the integrated circuit devices and electronic equipments includes a main factor of carrying away heat from the circuit board itself in the casing with high efficiency or carrying away heat from integrated circuit devices mounted on the circuit board with high efficiency. In a case where the performance of the electronic equipment is lowered or the electronic equipment is erroneously operated, it is difficult to determine that such an abnormal condition occurs because of abnormal temperature or abnormal power source voltage and thus detect the reason why such an abnormal condition occurs. For this reason, it is difficult to restore the equipment to the normal condition.